In many existing or proposed digital radiocommunication systems, for example TDMA systems such as GSM/EDGE, CDMA systems such as those defined in IS95, or wideband CDMA (W-CDMA) systems, there exists the possibility for a mobile terminal to transmit data at a variable rate. In general, it is desirable for the terminal to transmit at the highest data rate which is possible, given the available system capacity.
JP-A-9-326749 discloses a mobile communications device, for use in a TDMA system, in which packet data can be transmitted either continuously, that is in all three time slots of the TDMA system, or intermittently, that is in only one or two of the three TDMA slots. The device switches between continuous and intermittent mode in dependence on a temperature detected by a temperature sensor located in the vicinity of the power module of the device, which contains the amplifying stage.
However, this requires the use of a separate temperature sensor, which of course increases the number of components in the device.
Moreover, it is concerned only with the temperature of the electronic components of the device, which may not be the most important factor as far as the user is concerned.